Study of the viscoelastic properties of the agarose gel

Abstract Agarose is a biopolymer extracted from the red marine alga (Rhodophycees), it is widely used in agribusiness, pharmaceutical industry or as electrophoresis. The solution of this biopolymer in water gives rise to a more or less rigid solid mass called gel. This gel can be described as a matrix generating a macromolecular three-dimensional network. In this work, we exploit the experimental measurements of the stress undergone by the gel and the underlying deformation as a function of the different concentrations of the agarose to determine the creep function of this polymer in a linear regime according to the Boltzmann superposition principle. It turns out from the calculations that the gel is subjected to a delayed elasticity governed by Voigt’s analog model. This model allowed us to find the elastic modulus of the gel, and to determine the delay time and viscosity as function s of agarose concentrations.